emacs: add README (#7235)

plugins/emacs/README.md

@@ -0,0 +1,30 @@
+# Emacs plugin
+
+This plugin utilizes the Emacs daemon capability, allowing the user to quickly open frames, whether they are opened in a terminal via a ssh connection, or X frames opened on the same host. The plugin also provides some aliases for such operations.
+
+- You don't have the cost of starting Emacs all the time anymore
+- Opening a file is as fast as Emacs does not have anything else to do.
+- You can share opened buffered across opened frames.
+- Configuration changes made at runtime are applied to all frames.
+
+**NOTE:** requires Emacs 24 and newer.
+
+To use it, add emacs to the plugins array in your zshrc file:
+
+```zsh
+plugins=(... emacs)
+```
+
+## Aliases
+
+The plugin uses a custom launcher (which we'll call here `$EMACS_LAUNCHER`) that is just a wrapper around [`emacsclient`](https://www.emacswiki.org/emacs/EmacsClient).
+
+| Alias  | Command                                            | Description                                                    |
+|--------|----------------------------------------------------|----------------------------------------------------------------|
+| emacs  | `$EMACS_LAUNCHER --no-wait`                        | Opens a temporary emacsclient frame                            |
+| e      | `emacs`                                            | Same as emacs alias                                            |
+| te     | `$EMACS_LAUNCHER -nw`                              | Open terminal emacsclient                                      |
+| eeval  | `$EMACS_LAUNCHER --eval`                           | Same as `M-x eval` but from outside Emacs                      |
+| eframe | `emacsclient --alternate-editor "" --create-frame` | Create new X frame                                             |
+| efile  | -                                                  | Print the path to the file open in the current buffer          |
+| ecd    | -                                                  | Print the directory of the file open in the the current buffer |